Paper feeding mechanism



J e 1937. G. A. KNUDSEN PAPER FEEDING MECHANISM Filed Oct. 11, 1955 3 Sheets-Sheet 1 Galszay fljfnadsen ATTORNEY June 1, 1937. A, KNUDSEN 2,082,766

PAPER FEEDING MECHANI SM Filed Oct. 11, 1935 3 Sheets-Sheet 2 usiavfljzzzdseri ATTORNEY June 1,1937. 3, KNUDSEN 2,082,766

PAPER FEEDING MECHANI SM Filed Oct. 11, 1935 5 Sheets-Sheet s Patented June 1, 1937 UNITED STATES PATET OFFEQE 3 Claims.

This invention relates to mechanisms for feeding paper stock, such as used in conjunction with envelope forming and printing machines, folding machines and the like, and the primary object of my invention is to provide a paper feeder of simple and rugged construction, the novel operating principle of which will render efficient service under severe operating conditions and which will function to feed separate sheets into a machine in a dependable manner.

Another object of my invention is to provide a mechanism of the character indicated that is convenient and simple to maintain and operate in that a supply of paper stock may be placed into the feeder in the same arrangement in which it is usually provided and during the operation of the feeder without altering the setting or the adjustment of the machine in any Way.

The invention will be fully and comprehensively understood from a consideration of the following detailed description when read in connection with the accompanying drawings which form part of the application, with the understanding, however, that the improvement is capable of extended application and is not confined to the exact showing of the drawings nor to the precise construction described and, therefore, such changes and modifications may be made therein as do not affect the spirit of the invention nor exceed the scope thereof as expressed in the appended claims.

In the drawings:

Fig. 1 is a side elevational view of the drive side of my paper feeding mechanism.

Fig. 2 is a fragmentary side elevational view looking at the opposite side of the machine to that shown in Fig. 1.

Fig. 3 is a plan view of the feeding mechanism.

Fig. 4 is a detail view of a portion of the drive gearing, being a section taken on line 44 of Fig.

3; and

Fig. 5 is a longitudinal sectional View thru the paper feeder mechanism taken on the staggered line 5-5 of Fig. 3.

Reference is now had to the accompanying drawings fora more detailed description thereof in which the numeral 6 indicates a pair of brackets fixed to the feeder end of a printing or similar machine by which the support of my paper feeder mechanism is effected. Bearings! formed on the bracket 6 journal a roller shaft 8, which comprises the receiving end of a belt conveyor 9 by which the individual sheets of paper stock, envelopes or the like discharged from my feeder mechanism are conveyed into the printing machine.

The frame or body structure of my paper feeding mechanism comprises rigid side plates ll] and II secured in spaced parallelism with each other by suitable means, such as the cross rods l2 and the guide rod l3, which plates l9 have their supports on the brackets '6.

The receptacle or hopper for the stack of paper sheets M is so arranged as to support the paper at an angle slightly above the horizontal, as shown clearly in Fig. 5. The paper stack hopper comprises laterally adjustable end plates l5, from adjacent sides of which extend shelves IS, the latter being disposed at the desired angle. The shelves I6 are each slotted to adjustably hold guide blocks ll, which blocks are arcuately formed at their front surfaces for the purpose hereinafter described. By adjusting the end plates I5 which have their support on the rods 12 and I3 and by setting the guide blocks ll, the size of the paper hopper may be varied to suit the outside dimensions of the paper stock to be fed. When a narrow stock of paper is to be fed the shelves 16 provide sufficient support for same. When a wider stock is to be fed an auxiliary supporting block I6 is employed, as shown in Fig. 3, which block is supported on the cross bars l2 and I3. The lower end of the paper stack 14 rests against an inclined bar l8 which is held rigidly by the clamp [9 on the cross rod l2. The bar [8 is disposed preferably perpendicular to the shelves l6 and has its lower end arcuate in conformity to the curve of the adjacent surface of the blocks H. The arcuate end of the bar I8 in cooperation with the guide blocks I! cause the lowermost sheets of the stack I4 to be offset successively one from the other so that the lowermost sheets form a concave are at the forward end in substantial contact with the curved portion of the bar 18.

A friction cylinder 20 is arranged at the lower end of the stack l4, being so disposed that its periphery is tangential with the convex surface of the arcuate end of the bar l8 so that the ends of several of the bottom sheets of the stack l4 engage with the periphery of the cylinder 20 which is preferably formed of rubber to impart a resistance to the sliding of thesheets.

The cylinder 20 is vertically adjustable by being eccentrically mounted on its shaft 2|, which shaft is journalled in the side plates l0 and II. An end of the shaft 2| extends thru the plate H, at which end an adjustment arm 22 is affixed, see Fig. 2, the free end of which is adjustably anchored in a quadrant 23 to determine the desired position of the cylinder 20 consistent with the paper stock to be fed, see Fig. 5.

The feeding of the paper from the stack is accomplished by the withdrawal of a single sheet, specifically, the bottom sheet, which withdrawal is effected by the cooperative functioning of two sets of rollers. The first set, referred to as the 5 feed rollers, are indicated by numerals 24 and 25, the arrangement of which is shown more clearly in Fig. 3. The roller 25 is rotatably supported on its shaft 26, which shaft is journalled in the side plates Ill and H and is disposed so that its periphery is substantially tangential with the friction cylinder 26. Two rollers 24 are provided which are arranged at either side of the roller 25 and are carried on a shaft 21 journalled in the side plates H) and H. The rollers 24 and 25 are so arranged in alignment with the shelves l6 so that the stack of paper resting on same also rests at its middle portion on the rollers 24 and 25, which rollers have a frictional periphery.

The function of the feed rollers 24 and 25 is to effect the initial withdrawal of a single sheet from the bottom of the stack i l so that the end of the sheet is fed to the second set of rollers referred to as the pull out rollers 28, which rollers, being rotated continuously, complete the withdrawal of the sheet to deliver same onto the conveyor 9. The rollers 28 are rotated in unison by having their shafts connected thru the gears 29, the lower shaft being driven thru the sprocket 29. The pressure of the upper roller 28 against 30 the lower roller is variable by having its shaft journaled in slide blocks 30, supported in-slides formed in the side plates Ill and H, which blocks 30 are urged by their Springs 3! toward the lower roller 28, the springs 3| backing against a cap bar 32 between which is disposed a washer 33, see Fig, 5. Each of the slide blocks 30 is provided with a threaded rod 35, which projects thru the cap 32 and is fitted with an adjustable nut 35 by which the pressure of the upper roller 28 is adjusted. The locking of the nut 35 to the desired setting is effected by having its one end provided with a series of recesses 36 into which a ball 31 is urged by the spring 3! and the washer 33, the ball 31 being disposed in an aperture in the cap 32.

The drive for the feed rollers 24 and 25 will now be described, it being noted that these rollers are rotated intermittently in the direction indicated by the arrows in Fig. 5. The drive for the feed rollers is accomplished by a reciprocating gear rack it, see Fig. 1, which rack is in mesh with a gear M carried on the shaft 2'! and free to rotate independently of same. The gear 4| is integral with a sleeve 42 on which is formed 5 a ratchet wheel 43 engaged by a spring actuated pawl 44. The pawl M- is pivotally carried on a disc 45, the hub of which is provided with axially projecting clutch pins 46. The pins slidably engage in a clutch collar l! mounted to rotate freely on the shaft 2?. From the outer end of the clutch collar ll project pins 38, which pins are adapted to engage in notches 49 cut in an end collar 58 fixedly mounted on the shaft 21. From the clutch collar 41' extends radially a shifter arm 5! at the end of which a shifter rod 52 is connected, which rod extends to the opposite side of the feeder mechanism for convenience of operation and terminates in a knob 53. It is to be noted here that the sleeve 42 carrying gear 4! and ratchet wheel 13 is free to rotate on shaft 21 as is also the disc 45 and the clutch collar 47, which clutch, as shown in Fig. 3, is in disconnected position in that a swing arm 55 being pivotally mounted on the side plate H is engaged behind a shoulder of the knob 53. As

arm 5t releases the rod 52 the spring 55 surrounding the rod 52 urges the clutch collar 41 into engaged position, in which the pins 48 thereon are engaged in the notches 49 of the collar 50. As the gear rack 59 moves downwardly, the roller 2% is rotated in the direction of the arrow. At the upward stroke of the rack 40 the pawl 44 slips over the ratchet wheel 33, thus permitting the roller 2 to remain stationary. The drive for the feed rollers so far described provides for the intermittent rotation of the roller 2d.

The roller 25 is likewise intermittently rotated, being driven thru the train of gears illustrated in Fig. 4 comprising a drive gear 55 keyed to the shaft 2'5, an idler gear 5'? carried on a stud screw 58 and the driven gear 59, the latter being carried on the shaft The driven gear 59 is integral with a sleeve 58, which sleeve carries a ratchet wheel 6| in engagement with which is the spring actuated pawl 52 which is pivotally mounted on a disc 65, the latter being fixed to the shaft 26. The ratchet wheel 5i and the pawl 52 are so arranged that the feed roller 25 will be rotated intermittently in unison with the feed roller 24 thru the gear train shown in Fig. 4.

The initial withdrawal of the lowermost sheet of the stack M is eifected by the frictional engagement of the peripheries of the feed rollers 24 and 25 with same, the drives of which are effected by the downward movement of the gear rack All and the associated mechanism. As the lowermost sheet is further withdrawn from the stack its forward end becomes engaged in the pull out rollers 28, which rollers complete the withdrawal, during which the sheet being with-.

drawn is still in contact with the feed rollers 24 and 25, whence their respective ratchet mechanisms permit the rotation of these rollers inde pendent of their respective drives. As the rear end of the sheet being withdrawn leaves the feed roller 24, this roller comes in contact with the succeeding sheet. The momentum of the roller 24 at this stage of operation may tend to elfect the initial feeding of the second sheet before thev first sheet is completely withdrawn unless the rotation of the feed roller 24 be prevented. To this end a braking mechanism, shown in Fig. 3, is provided. This braking mechanism comprises a pulley 65 embodying a brake drum fixed to the shaft 21. A flexible belt 66 of frictional material such as leather is. looped over so as to be in contact with the periphery of pulley 65. One end of the belt 65 is fixed to the side plate It], the other end being joined to a tension spring 61, which spring is anchored on the side plate Ill. The tension of spring 6'! holds the belt 66 in frictional engagement with the periphery of pulley 65 so that the free rotation of feed roller 2 is retarded.

The function of the friction cylinder 20 will now be described, during which attention is directed to Fig. 5. The cylinder 20 is to be so positioned with relation to the feed roller 25 by adjustment of the arm 32 so that ample space is provided between these members to permit the free passage of only the bottom sheet, the succeeding sheets being retarded by having their ends engaged with the periphery of the cylinder 20. In this respect the offset arrangement of the lowermost sheets of the stack l4 due to the curve of the bar it; and the guide blocks H, as

' well as the disposition of the cylinder 20, assists in the proper functioning of the feed rollers to withdraw a single sheet in that the second sheet from the bottom is in contact with the friction cylinder 20 and therefore its tendency to be Withdrawn is counteracted by its frictional engagement with the cylinder 20. At the same time the second sheet affords a frictionless cushioning for the bottom sheet during its Withdrawal.

What is claimed as new is:

1. In a paper feeding mechanism, a magazine adapted to support a stack of paper sheets in substantially horizontal but slightly inclined position, said magazine comprising a pair of relatively adjustable vertical side plates having opposed shelves extending laterally therefrom in support of the longitudinal edges only of the stack at the bottom thereof, a substantially vertical member against which the lower end of the paper sheets may rest, a friction cylinder at the bottom of said member, said member terminating in an arc tangential with the periphery of said cylinder, a plurality of intermittently rotated .feed rollers intermediate said side plates in support of the longitudinal center only of said paper stack, means for intermittently rotating said feed rollers, one of said feed rollcrs having its periphery in tangential relation to said cylinder, said feed rollers being adapted to eifect the initial withdrawal of the lowermost sheet, and a pair of continuously rotated pull-out rollers beyond said magazine adapted to grip the leading edge of the paper sheet being fed to completely withdraw same from the magazine.

2. In a paper feeding mechanism, a magazine adapted to support a stack of paper sheets in substantially horizontal but slightly inclined position, said magazine comprising a pair of relatively adjustable vertical side plates having opposed shelves extending laterally therefrom in support of the longitudinal edges only of the stack at the bottom thereof, a substantially vertical member against which the lower end of the paper sheets may rest, a friction cylinder at the bottom of said member, said member terminating in an arc tangential with the periphery of said cylinder, a plurality of intermittently rotated feed rollers intermediate said side plates in support of the longitudinal center only of said paper stack, means for intermittently rotating said feed rollers, one of said feed rollers having its periphery in tangential relation to said cylinder, said feed rollers being adapted to effect the initial withdrawal of the lowermost sheet, and a of continuously rotated pull-out rollers beyond said magazine adapted to grip the leading edge of the paper sheet being fed to completely Withdraw same from the magazine, said side plate shelves including position adjustable guide blocks thereon adapted to engage the rear end of the stack, the engaging surface of each of said blocks being shaped in substantial counterpart to the combined contour of said member and the friction cylinder associated therewith.

3. In a paper feeding mechanism, a magazine for support of a stack of paper sheets in substantially horizontal but slightly inclined position, a member against which the lower end of the stack of sheets may rest, a friction cylinder at the lower end of said member, a feed roller below said cylinder, a pair of continuously rotated pull-out rollers in front of said feed roller, and means for adjusting the position of one of said pull-out rollers comprising spring-backed slide blocks which journal the shafts of said rollers, a threaded rod actuating said slide blocks and having a collar threadedly engaged thereon including a series of recesses, and a detent backed by said block spring engaging said recesses.

GUSTAV A. KNUDSEN. 

